import React, { useEffect, useState } from 'react'

export default function App() {
  const [count, setCount] = useState(0);
  const [isHot, setIsHot] = useState(true);

  useEffect(() => {
    console.log("isHot执行了");
    return () => {
      console.log("isHot的Effect卸载函数" + count);
    }
  }, [isHot, count])

  useEffect(() => {
    console.log("count执行了");
  }, [count])

  


  return (
    <div>
      <h1>count的值是{count}</h1>
      <button onClick={() => {setCount(count + 1)}}>累加</button>
      <hr />
      <h1>天气真的{isHot ? '热啊' : '冷啊'}</h1>
      <button onClick={() => {setIsHot(!isHot)}}>变温</button>
    </div>
  )
}
 